Yes, it is entirely possible to purchase tax lien certificates via the mail. Keep in mind that the type of purchase opportunity which you will be dealing with will be called a resale or strike off type of purchase. A resale or strike off purchase opportunity is created when a tax certificate or tax deed is not sold at the original auction. The certificate is then struck off to the lead entity which started the lawsuit to collect the delinquent taxes.

The property (if its a tax deed auction...like in Texas or California) or the certificate (if its a certificate sale...as in most other states) will be sold then to bidders whose offers on the deed or certificate are accepted by the taxing entity in charge of the resale.

As far as Canadian bidders there is no requirement which I am aware of that you must be a citizen of the United States. Really Chris your biggest concern should be to determine something about the property. I tell all investors to think of tax sale investing as just another way to find discount properties. It follows that as with any form of real estate investment you must do your research. While alot of "guru's" and late night informerical marketing personalities like to make real estate investing seem easy and fail safe, in reality you must do you research.

As part of your research I would ALWAYS suggest viewing the property before you purchase a certificate or deed associated with the parcel of land. Although bidding and buying via the mail is possible, unless you have someone who can view the property for you, then you are increasing your risk.

Chris, if you are interested in higher yields you should check to see if there are any tax lien certificate funds (i.e., like mutual funds) available through some brokerge houses around you. Although you won't make near what you could investing in liens yourself...if you are unable to view properties, but would like higher yields then I have presented you with another option.

Best of Luck and keep us all informed on your progress!